Zabbix active agent not working

[alaahil]

We are in the process of evaluating zabbix to be used for monitoring and we have been trying a small setup to get more familiarized. I have encountered a problem when trying to do active checks through zabbix agent.

my setup:
zabbix server and database are installed on WSL

Zabbix agent installed on windows server
we are not using proxies in this minimized setup

passive checks are working normally and also I tested traps with senders and everything is working well. However, when using the "zabbix agent (active)" interface, no data is sent to the server.

on windows server the zabbix_agentd.conf looks like that
#
# Mandatory: no
# Default:
# DisableActive=0
# DisableActive=0
# ServerActive=

ServerActive=10.60.1.254:10056

Then when starting the zabbix agent service I get the logs below:
3156:20231020:161613.681 agent #0 started [main process]
4568:20231020:161613.682 agent #2 started[listener #1]
7912:20231020:161613.683 agent #3 started[listener #2]
6728:20231020:161613.683 agent #4 started[listener #3]
7768:20231020:161613.683 agent #5 started [active checks #1]
6204:20231020:161613.684 agent #1 started [collector]
7768:20231020:161616.695 Unable to connect to [10.60.1.254]:10056 [cannot connect to [[10.60.1.254]:10056]: (null)]
7768:20231020:161616.696 Unable to send heartbeat message to [10.60.1.254]:10056 [cannot connect to [[10.60.1.254]:10056]: (null)]

The ports are open and the passive interface for the same zabbix agent is working well. Any thoughts pleas?

[vijayk]

Make change in agentd.config

Server: zabbixserver ip
ServerActive=zabbixserver ip
HostName: {YourServerHostName} (Same mention it in item hostname)

[alaahil]

I am still getting the same error after doing the above change (the only issue is that connection is being attempted on default port now but same failure)

[vijayk]

Can you please share the host configuration screenshot and agentd.config file for better understand?

[alaahil]

Yes, certainly.
Below is the config file from the windows machine

# This is a configuration file for Zabbix agent service (Windows)
# To get more information about Zabbix, visit http://www.zabbix.com

############ GENERAL PARAMETERS #################

### Option: LogType
# Specifies where log messages are written to:
# system - Windows event log
# file - file specified with LogFile parameter
# console - standard output
#
# Mandatory: no
# Default:
# LogType=file


### Option: LogFile
# Log file name for LogType 'file' parameter.
#
# Mandatory: no
# Default:
# LogFile=

LogFile=C:\Program Files\Zabbix Agent\zabbix_agentd.log

### Option: LogFileSize
# Maximum size of log file in MB.
# 0 - disable automatic log rotation.
#
# Mandatory: no
# Range: 0-1024
# Default:
# LogFileSize=1

### Option: DebugLevel
# Specifies debug level:
# 0 - basic information about starting and stopping of Zabbix processes
# 1 - critical information
# 2 - error information
# 3 - warnings
# 4 - for debugging (produces lots of information)
# 5 - extended debugging (produces even more information)
#
# Mandatory: no
# Range: 0-5
# Default:
# DebugLevel=3

### Option: SourceIP
# Source IP address for outgoing connections.
#
# Mandatory: no
# Default:
# SourceIP=

### Option: AllowKey
# Allow execution of item keys matching pattern.
# Multiple keys matching rules may be defined in combination with DenyKey.
# Key pattern is wildcard expression, which support "*" character to match any number of any characters in certain position. It might be used in both key name and key arguments.
# Parameters are processed one by one according their appearance order.
# If no AllowKey or DenyKey rules defined, all keys are allowed.
#
# Mandatory: no

### Option: DenyKey
# Deny execution of items keys matching pattern.
# Multiple keys matching rules may be defined in combination with AllowKey.
# Key pattern is wildcard expression, which support "*" character to match any number of any characters in certain position. It might be used in both key name and key arguments.
# Parameters are processed one by one according their appearance order.
# If no AllowKey or DenyKey rules defined, all keys are allowed.
# Unless another system.run[*] rule is specified DenyKey=system.run[*] is added by default.
#
# Mandatory: no
# Default:
# DenyKey=system.run[*]



### Option: EnableRemoteCommands - Deprecated, use AllowKey=system.run[*] or DenyKey=system.run[*] instead
# Internal alias for AllowKey/DenyKey parameters depending on value:
# 0 - DenyKey=system.run[*]
# 1 - AllowKey=system.run[*]
#
# Mandatory: no

### Option: LogRemoteCommands
# Enable logging of executed shell commands as warnings.
# 0 - disabled
# 1 - enabled
#
# Mandatory: no
# Default:
# LogRemoteCommands=0

##### Passive checks related

### Option: Server
# List of comma delimited IP addresses, optionally in CIDR notation, or DNS names of Zabbix servers and Zabbix proxies.
# Incoming connections will be accepted only from the hosts listed here.
# If IPv6 support is enabled then '127.0.0.1', '::127.0.0.1', '::ffff:127.0.0.1' are treated equally and '::/0' will allow any IPv4 or IPv6 address.
# '0.0.0.0/0' can be used to allow any IPv4 address.
# Example: Server=127.0.0.1,192.168.1.0/24,::1,2001:db8::/32,zabbix.domain
#
# Mandatory: yes, if StartAgents is not explicitly set to 0
# Default:
# Server=

Server=10.60.1.254

### Option: ListenPort
# Agent will listen on this port for connections from the server.
#
# Mandatory: no
# Range: 1024-32767
# Default:
# ListenPort=10050
ListenPort=10053

### Option: ListenIP
# List of comma delimited IP addresses that the agent should listen on.
# First IP address is sent to Zabbix server if connecting to it to retrieve list of active checks.
#
# Mandatory: no
# Default:
# ListenIP=0.0.0.0


### Option: StartAgents
# Number of pre-forked instances of zabbix_agentd that process passive checks.
# If set to 0, disables passive checks and the agent will not listen on any TCP port.
#
# Mandatory: no
# Range: 0-100
# Default:
# StartAgents=3

##### Active checks related

### Option: ServerActive
# Zabbix server/proxy address or cluster configuration to get active checks from.
# Server/proxy address is IP address or DNS name and optional port separated by colon.
# Cluster configuration is one or more server addresses separated by semicolon.
# Multiple Zabbix servers/clusters and Zabbix proxies can be specified, separated by comma.
# More than one Zabbix proxy should not be specified from each Zabbix server/cluster.
# If Zabbix proxy is specified then Zabbix server/cluster for that proxy should not be specified.
# Multiple comma-delimited addresses can be provided to use several independent Zabbix servers in parallel. Spaces are allowed.
# If port is not specified, default port is used.
# IPv6 addresses must be enclosed in square brackets if port for that host is specified.
# If port is not specified, square brackets for IPv6 addresses are optional.
# If this parameter is not specified, active checks are disabled.
# Example for Zabbix proxy:
# ServerActive=127.0.0.1:10051
# Example for multiple servers:
# ServerActive=127.0.0.1:20051,zabbix.domain,[::1]:30051,::1,[12fc::1]
# Example for high availability:
# ServerActive=zabbix.cluster.node1;zabbix.cluster.n ode2:20051;zabbix.cluster.node3
# Example for high availability with two clusters and one server:
# ServerActive=zabbix.cluster.node1;zabbix.cluster.n ode2:20051,zabbix.cluster2.node1;zabbix.cluster2.n ode2,zabbix.domain
#
# Mandatory: no
# Default:
# DisableActive=0
# DisableActive=0
# ServerActive=

ServerActive=10.60.1.254

### Option: Hostname
# List of comma delimited unique, case sensitive hostnames.
# Required for active checks and must match hostnames as configured on the server.
# Value is acquired from HostnameItem if undefined.
#
# Mandatory: no
# Default:
# Hostname=

Hostname=MWP-ADCON01

### Option: HostnameItem
# Item used for generating Hostname if it is undefined. Ignored if Hostname is defined.
# Does not support UserParameters or aliases.
#
# Mandatory: no
# Default:
# HostnameItem=system.hostname

### Option: HostMetadata
# Optional parameter that defines host metadata.
# Host metadata is used at host auto-registration process.
# An agent will issue an error and not start if the value is over limit of 2034 bytes.
# If not defined, value will be acquired from HostMetadataItem.
#
# Mandatory: no
# Range: 0-2034 bytes
# Default:
# HostMetadata=


### Option: HostMetadataItem
# Optional parameter that defines an item used for getting host metadata.
# Host metadata is used at host auto-registration process.
# During an auto-registration request an agent will log a warning message if
# the value returned by specified item is over limit of 65535 characters.
# This option is only used when HostMetadata is not defined.
#
# Mandatory: no
# Default:
# HostMetadataItem=


### Option: HostInterface
# Optional parameter that defines host interface.
# Host interface is used at host auto-registration process.
# An agent will issue an error and not start if the value is over limit of 255 characters.
# If not defined, value will be acquired from HostInterfaceItem.
#
# Mandatory: no
# Range: 0-255 characters
# Default:
# HostInterface=


### Option: HostInterfaceItem
# Optional parameter that defines an item used for getting host interface.
# Host interface is used at host auto-registration process.
# During an auto-registration request an agent will log a warning message if
# the value returned by specified item is over limit of 255 characters.
# This option is only used when HostInterface is not defined.
#
# Mandatory: no
# Default:
# HostInterfaceItem=

### Option: RefreshActiveChecks
# How often list of active checks is refreshed, in seconds.
#
# Mandatory: no
# Range: 1-86400
# Default:
# RefreshActiveChecks=5

### Option: BufferSend
# Do not keep data longer than N seconds in buffer.
#
# Mandatory: no
# Range: 1-3600
# Default:
# BufferSend=5

### Option: BufferSize
# Maximum number of values in a memory buffer. The agent will send
# all collected data to Zabbix server or Proxy if the buffer is full.
#
# Mandatory: no
# Range: 2-65535
# Default:
# BufferSize=100

### Option: MaxLinesPerSecond
# Maximum number of new lines the agent will send per second to Zabbix Server
# or Proxy processing 'log', 'logrt' and 'eventlog' active checks.
# The provided value will be overridden by the parameter 'maxlines',
# provided in 'log', 'logrt' or 'eventlog' item keys.
#
# Mandatory: no
# Range: 1-1000
# Default:
# MaxLinesPerSecond=20

### Option: HeartbeatFrequency
# Frequency of heartbeat messages in seconds.
# Used for monitoring availability of active checks.
# 0 - heartbeat messages disabled.
#
# Mandatory: no
# Range: 0-3600
# Default: 60
# HeartbeatFrequency=

############ ADVANCED PARAMETERS #################

### Option: Alias
# Sets an alias for an item key. It can be used to substitute long and complex item key with a smaller and simpler one.
# Multiple Alias parameters may be present. Multiple parameters with the same Alias key are not allowed.
# Different Alias keys may reference the same item key.
# For example, to retrieve paging file usage in percents from the server:
# Alias=pg_usageerf_counter[\Paging File(_Total)\% Usage]
# Now shorthand key pg_usage may be used to retrieve data.
# Aliases can be used in HostMetadataItem but not in HostnameItem or PerfCounter parameters.
#
# Mandatory: no
# Range:
# Default:

### Option: Timeout
# Spend no more than Timeout seconds on processing.
#
# Mandatory: no
# Range: 1-30
# Default:
# Timeout=3


### Option: PerfCounter
# Syntax: <parameter_name>,"<perf_counter_path>",<period>
# Defines new parameter <parameter_name> which is an average value for system performance counter <perf_counter_path> for the specified time period <period> (in seconds).
# For example, if you wish to receive average number of processor interrupts per second for last minute, you can define new parameter "interrupts" as following:
# PerfCounter = interrupts,"\Processor(0)\Interrupts/sec",60
# Please note double quotes around performance counter path.
# Samples for calculating average value will be taken every second.
# You may run "typeperf -qx" to get list of all performance counters available in Windows.
#
# Mandatory: no
# Range:
# Default:

### Option: Include
# You may include individual files in the configuration file.
#
# Mandatory: no
# Default:
# Include=
Include=C:\Program Files\Zabbix Agent\zabbix_agentd.d\

# Include=c:\zabbix\zabbix_agentd.userparams.conf
# Include=c:\zabbix\zabbix_agentd.conf.d\
# Include=c:\zabbix\zabbix_agentd.conf.d\*.conf

####### USER-DEFINED MONITORED PARAMETERS #######

### Option: UnsafeUserParameters
# Allow all characters to be passed in arguments to user-defined parameters.
# The following characters are not allowed:
# \ ' " ` * ? [ ] { } ~ $ ! & ; ( ) < > | # @
# Additionally, newline characters are not allowed.
# 0 - do not allow
# 1 - allow
#
# Mandatory: no
# Range: 0-1
# Default:
# UnsafeUserParameters=0

### Option: UserParameter
# User-defined parameter to monitor. There can be several user-defined parameters.
# Format: UserParameter=<key>,<shell command>
#
# Mandatory: no
# Default:
# UserParameter=

### Option: UserParameterDir
# Directory to execute UserParameter commands from. Only one entry is allowed.
# When executing UserParameter commands the agent will change the working directory to the one
# specified in the UserParameterDir option.
# This way UserParameter commands can be specified using the relative ./ prefix.
#
# Mandatory: no
# Default:
# UserParameterDir=

####### TLS-RELATED PARAMETERS #######

### Option: TLSConnect
# How the agent should connect to server or proxy. Used for active checks.
# Only one value can be specified:
# unencrypted - connect without encryption
# psk - connect using TLS and a pre-shared key
# cert - connect using TLS and a certificate
#
# Mandatory: yes, if TLS certificate or PSK parameters are defined (even for 'unencrypted' connection)
# Default:
# TLSConnect=unencrypted


### Option: TLSAccept
# What incoming connections to accept.
# Multiple values can be specified, separated by comma:
# unencrypted - accept connections without encryption
# psk - accept connections secured with TLS and a pre-shared key
# cert - accept connections secured with TLS and a certificate
#
# Mandatory: yes, if TLS certificate or PSK parameters are defined (even for 'unencrypted' connection)
# Default:
# TLSAccept=unencrypted


### Option: TLSCAFile
# Full pathname of a file containing the top-level CA(s) certificates for
# peer certificate verification.
#
# Mandatory: no
# Default:
# TLSCAFile=


### Option: TLSCRLFile
# Full pathname of a file containing revoked certificates.
#
# Mandatory: no
# Default:
# TLSCRLFile=


### Option: TLSServerCertIssuer
# Allowed server certificate issuer.
#
# Mandatory: no
# Default:
# TLSServerCertIssuer=


### Option: TLSServerCertSubject
# Allowed server certificate subject.
#
# Mandatory: no
# Default:
# TLSServerCertSubject=


### Option: TLSCertFile
# Full pathname of a file containing the agent certificate or certificate chain.
#
# Mandatory: no
# Default:
# TLSCertFile=


### Option: TLSKeyFile
# Full pathname of a file containing the agent private key.
#
# Mandatory: no
# Default:
# TLSKeyFile=


### Option: TLSPSKIdentity
# Unique, case sensitive string used to identify the pre-shared key.
#
# Mandatory: no
# Default:
# TLSPSKIdentity=


### Option: TLSPSKFile
# Full pathname of a file containing the pre-shared key.
#
# Mandatory: no
# Default:
# TLSPSKFile=


####### For advanced users - TLS ciphersuite selection criteria #######

### Option: TLSCipherCert13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for certificate-based encryption.
#
# Mandatory: no
# Default:
# TLSCipherCert13=

### Option: TLSCipherCert
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for certificate-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL:+CTYPE-X.509
# Example for OpenSSL:
# EECDH+aRSA+AES128:RSA+aRSA+AES128
#
# Mandatory: no
# Default:
# TLSCipherCert=

### Option: TLSCipherPSK13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for PSK-based encryption.
# Example:
# TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA25 6
#
# Mandatory: no
# Default:
# TLSCipherPSK13=

### Option: TLSCipherPSK
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for PSK-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL
# Example for OpenSSL:
# kECDHEPSK+AES128:kPSK+AES128
#
# Mandatory: no
# Default:
# TLSCipherPSK=

### Option: TLSCipherAll13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
# Example:
# TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA25 6:TLS_AES_128_GCM_SHA256
#
# Mandatory: no
# Default:
# TLSCipherAll13=

### Option: TLSCipherAll
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL:+CTYPE-X.509
# Example for OpenSSL:
# EECDH+aRSA+AES128:RSA+aRSA+AES128:kECDHEPSK+AES128 :kPSK+AES128
#
# Mandatory: no
# Default:
# TLSCipherAll=

####### For advanced users - TCP-related fine-tuning parameters #######

## Option: ListenBacklog
# The maximum number of pending connections in the queue. This parameter is passed to
# listen() function as argument 'backlog' (see "man listen").
#
# Mandatory: no
# Range: 0 - INT_MAX (depends on system, too large values may be silently truncated to implementation-specified maximum)
# Default: SOMAXCONN (hard-coded constant, depends on system)
# ListenBacklog=

#DisableActive=0
#DisablePassive=0

[vijayk]

Yes, certainly.
Below is the config file from the windows machine

# This is a configuration file for Zabbix agent service (Windows)
# To get more information about Zabbix, visit http://www.zabbix.com

############ GENERAL PARAMETERS #################

### Option: LogType
# Specifies where log messages are written to:
# system - Windows event log
# file - file specified with LogFile parameter
# console - standard output
#
# Mandatory: no
# Default:
# LogType=file


### Option: LogFile
# Log file name for LogType 'file' parameter.
#
# Mandatory: no
# Default:
# LogFile=

LogFile=C:\Program Files\Zabbix Agent\zabbix_agentd.log

### Option: LogFileSize
# Maximum size of log file in MB.
# 0 - disable automatic log rotation.
#
# Mandatory: no
# Range: 0-1024
# Default:
# LogFileSize=1

### Option: DebugLevel
# Specifies debug level:
# 0 - basic information about starting and stopping of Zabbix processes
# 1 - critical information
# 2 - error information
# 3 - warnings
# 4 - for debugging (produces lots of information)
# 5 - extended debugging (produces even more information)
#
# Mandatory: no
# Range: 0-5
# Default:
# DebugLevel=3

### Option: SourceIP
# Source IP address for outgoing connections.
#
# Mandatory: no
# Default:
# SourceIP=

### Option: AllowKey
# Allow execution of item keys matching pattern.
# Multiple keys matching rules may be defined in combination with DenyKey.
# Key pattern is wildcard expression, which support "*" character to match any number of any characters in certain position. It might be used in both key name and key arguments.
# Parameters are processed one by one according their appearance order.
# If no AllowKey or DenyKey rules defined, all keys are allowed.
#
# Mandatory: no

### Option: DenyKey
# Deny execution of items keys matching pattern.
# Multiple keys matching rules may be defined in combination with AllowKey.
# Key pattern is wildcard expression, which support "*" character to match any number of any characters in certain position. It might be used in both key name and key arguments.
# Parameters are processed one by one according their appearance order.
# If no AllowKey or DenyKey rules defined, all keys are allowed.
# Unless another system.run[*] rule is specified DenyKey=system.run[*] is added by default.
#
# Mandatory: no
# Default:
# DenyKey=system.run[*]



### Option: EnableRemoteCommands - Deprecated, use AllowKey=system.run[*] or DenyKey=system.run[*] instead
# Internal alias for AllowKey/DenyKey parameters depending on value:
# 0 - DenyKey=system.run[*]
# 1 - AllowKey=system.run[*]
#
# Mandatory: no

### Option: LogRemoteCommands
# Enable logging of executed shell commands as warnings.
# 0 - disabled
# 1 - enabled
#
# Mandatory: no
# Default:
# LogRemoteCommands=0

##### Passive checks related

### Option: Server
# List of comma delimited IP addresses, optionally in CIDR notation, or DNS names of Zabbix servers and Zabbix proxies.
# Incoming connections will be accepted only from the hosts listed here.
# If IPv6 support is enabled then '127.0.0.1', '::127.0.0.1', '::ffff:127.0.0.1' are treated equally and '::/0' will allow any IPv4 or IPv6 address.
# '0.0.0.0/0' can be used to allow any IPv4 address.
# Example: Server=127.0.0.1,192.168.1.0/24,::1,2001:db8::/32,zabbix.domain
#
# Mandatory: yes, if StartAgents is not explicitly set to 0
# Default:
# Server=

Server=10.60.1.254

### Option: ListenPort
# Agent will listen on this port for connections from the server.
#
# Mandatory: no
# Range: 1024-32767
# Default:
# ListenPort=10050
ListenPort=10053

### Option: ListenIP
# List of comma delimited IP addresses that the agent should listen on.
# First IP address is sent to Zabbix server if connecting to it to retrieve list of active checks.
#
# Mandatory: no
# Default:
# ListenIP=0.0.0.0


### Option: StartAgents
# Number of pre-forked instances of zabbix_agentd that process passive checks.
# If set to 0, disables passive checks and the agent will not listen on any TCP port.
#
# Mandatory: no
# Range: 0-100
# Default:
# StartAgents=3

##### Active checks related

### Option: ServerActive
# Zabbix server/proxy address or cluster configuration to get active checks from.
# Server/proxy address is IP address or DNS name and optional port separated by colon.
# Cluster configuration is one or more server addresses separated by semicolon.
# Multiple Zabbix servers/clusters and Zabbix proxies can be specified, separated by comma.
# More than one Zabbix proxy should not be specified from each Zabbix server/cluster.
# If Zabbix proxy is specified then Zabbix server/cluster for that proxy should not be specified.
# Multiple comma-delimited addresses can be provided to use several independent Zabbix servers in parallel. Spaces are allowed.
# If port is not specified, default port is used.
# IPv6 addresses must be enclosed in square brackets if port for that host is specified.
# If port is not specified, square brackets for IPv6 addresses are optional.
# If this parameter is not specified, active checks are disabled.
# Example for Zabbix proxy:
# ServerActive=127.0.0.1:10051
# Example for multiple servers:
# ServerActive=127.0.0.1:20051,zabbix.domain,[::1]:30051,::1,[12fc::1]
# Example for high availability:
# ServerActive=zabbix.cluster.node1;zabbix.cluster.n ode2:20051;zabbix.cluster.node3
# Example for high availability with two clusters and one server:
# ServerActive=zabbix.cluster.node1;zabbix.cluster.n ode2:20051,zabbix.cluster2.node1;zabbix.cluster2.n ode2,zabbix.domain
#
# Mandatory: no
# Default:
# DisableActive=0
# DisableActive=0
# ServerActive=

ServerActive=10.60.1.254

### Option: Hostname
# List of comma delimited unique, case sensitive hostnames.
# Required for active checks and must match hostnames as configured on the server.
# Value is acquired from HostnameItem if undefined.
#
# Mandatory: no
# Default:
# Hostname=

Hostname=MWP-ADCON01

### Option: HostnameItem
# Item used for generating Hostname if it is undefined. Ignored if Hostname is defined.
# Does not support UserParameters or aliases.
#
# Mandatory: no
# Default:
# HostnameItem=system.hostname

### Option: HostMetadata
# Optional parameter that defines host metadata.
# Host metadata is used at host auto-registration process.
# An agent will issue an error and not start if the value is over limit of 2034 bytes.
# If not defined, value will be acquired from HostMetadataItem.
#
# Mandatory: no
# Range: 0-2034 bytes
# Default:
# HostMetadata=


### Option: HostMetadataItem
# Optional parameter that defines an item used for getting host metadata.
# Host metadata is used at host auto-registration process.
# During an auto-registration request an agent will log a warning message if
# the value returned by specified item is over limit of 65535 characters.
# This option is only used when HostMetadata is not defined.
#
# Mandatory: no
# Default:
# HostMetadataItem=


### Option: HostInterface
# Optional parameter that defines host interface.
# Host interface is used at host auto-registration process.
# An agent will issue an error and not start if the value is over limit of 255 characters.
# If not defined, value will be acquired from HostInterfaceItem.
#
# Mandatory: no
# Range: 0-255 characters
# Default:
# HostInterface=


### Option: HostInterfaceItem
# Optional parameter that defines an item used for getting host interface.
# Host interface is used at host auto-registration process.
# During an auto-registration request an agent will log a warning message if
# the value returned by specified item is over limit of 255 characters.
# This option is only used when HostInterface is not defined.
#
# Mandatory: no
# Default:
# HostInterfaceItem=

### Option: RefreshActiveChecks
# How often list of active checks is refreshed, in seconds.
#
# Mandatory: no
# Range: 1-86400
# Default:
# RefreshActiveChecks=5

### Option: BufferSend
# Do not keep data longer than N seconds in buffer.
#
# Mandatory: no
# Range: 1-3600
# Default:
# BufferSend=5

### Option: BufferSize
# Maximum number of values in a memory buffer. The agent will send
# all collected data to Zabbix server or Proxy if the buffer is full.
#
# Mandatory: no
# Range: 2-65535
# Default:
# BufferSize=100

### Option: MaxLinesPerSecond
# Maximum number of new lines the agent will send per second to Zabbix Server
# or Proxy processing 'log', 'logrt' and 'eventlog' active checks.
# The provided value will be overridden by the parameter 'maxlines',
# provided in 'log', 'logrt' or 'eventlog' item keys.
#
# Mandatory: no
# Range: 1-1000
# Default:
# MaxLinesPerSecond=20

### Option: HeartbeatFrequency
# Frequency of heartbeat messages in seconds.
# Used for monitoring availability of active checks.
# 0 - heartbeat messages disabled.
#
# Mandatory: no
# Range: 0-3600
# Default: 60
# HeartbeatFrequency=

############ ADVANCED PARAMETERS #################

### Option: Alias
# Sets an alias for an item key. It can be used to substitute long and complex item key with a smaller and simpler one.
# Multiple Alias parameters may be present. Multiple parameters with the same Alias key are not allowed.
# Different Alias keys may reference the same item key.
# For example, to retrieve paging file usage in percents from the server:
# Alias=pg_usageerf_counter[\Paging File(_Total)\% Usage]
# Now shorthand key pg_usage may be used to retrieve data.
# Aliases can be used in HostMetadataItem but not in HostnameItem or PerfCounter parameters.
#
# Mandatory: no
# Range:
# Default:

### Option: Timeout
# Spend no more than Timeout seconds on processing.
#
# Mandatory: no
# Range: 1-30
# Default:
# Timeout=3


### Option: PerfCounter
# Syntax: <parameter_name>,"<perf_counter_path>",<period>
# Defines new parameter <parameter_name> which is an average value for system performance counter <perf_counter_path> for the specified time period <period> (in seconds).
# For example, if you wish to receive average number of processor interrupts per second for last minute, you can define new parameter "interrupts" as following:
# PerfCounter = interrupts,"\Processor(0)\Interrupts/sec",60
# Please note double quotes around performance counter path.
# Samples for calculating average value will be taken every second.
# You may run "typeperf -qx" to get list of all performance counters available in Windows.
#
# Mandatory: no
# Range:
# Default:

### Option: Include
# You may include individual files in the configuration file.
#
# Mandatory: no
# Default:
# Include=
Include=C:\Program Files\Zabbix Agent\zabbix_agentd.d\

# Include=c:\zabbix\zabbix_agentd.userparams.conf
# Include=c:\zabbix\zabbix_agentd.conf.d\
# Include=c:\zabbix\zabbix_agentd.conf.d\*.conf

####### USER-DEFINED MONITORED PARAMETERS #######

### Option: UnsafeUserParameters
# Allow all characters to be passed in arguments to user-defined parameters.
# The following characters are not allowed:
# \ ' " ` * ? [ ] { } ~ $ ! & ; ( ) < > | # @
# Additionally, newline characters are not allowed.
# 0 - do not allow
# 1 - allow
#
# Mandatory: no
# Range: 0-1
# Default:
# UnsafeUserParameters=0

### Option: UserParameter
# User-defined parameter to monitor. There can be several user-defined parameters.
# Format: UserParameter=<key>,<shell command>
#
# Mandatory: no
# Default:
# UserParameter=

### Option: UserParameterDir
# Directory to execute UserParameter commands from. Only one entry is allowed.
# When executing UserParameter commands the agent will change the working directory to the one
# specified in the UserParameterDir option.
# This way UserParameter commands can be specified using the relative ./ prefix.
#
# Mandatory: no
# Default:
# UserParameterDir=

####### TLS-RELATED PARAMETERS #######

### Option: TLSConnect
# How the agent should connect to server or proxy. Used for active checks.
# Only one value can be specified:
# unencrypted - connect without encryption
# psk - connect using TLS and a pre-shared key
# cert - connect using TLS and a certificate
#
# Mandatory: yes, if TLS certificate or PSK parameters are defined (even for 'unencrypted' connection)
# Default:
# TLSConnect=unencrypted


### Option: TLSAccept
# What incoming connections to accept.
# Multiple values can be specified, separated by comma:
# unencrypted - accept connections without encryption
# psk - accept connections secured with TLS and a pre-shared key
# cert - accept connections secured with TLS and a certificate
#
# Mandatory: yes, if TLS certificate or PSK parameters are defined (even for 'unencrypted' connection)
# Default:
# TLSAccept=unencrypted


### Option: TLSCAFile
# Full pathname of a file containing the top-level CA(s) certificates for
# peer certificate verification.
#
# Mandatory: no
# Default:
# TLSCAFile=


### Option: TLSCRLFile
# Full pathname of a file containing revoked certificates.
#
# Mandatory: no
# Default:
# TLSCRLFile=


### Option: TLSServerCertIssuer
# Allowed server certificate issuer.
#
# Mandatory: no
# Default:
# TLSServerCertIssuer=


### Option: TLSServerCertSubject
# Allowed server certificate subject.
#
# Mandatory: no
# Default:
# TLSServerCertSubject=


### Option: TLSCertFile
# Full pathname of a file containing the agent certificate or certificate chain.
#
# Mandatory: no
# Default:
# TLSCertFile=


### Option: TLSKeyFile
# Full pathname of a file containing the agent private key.
#
# Mandatory: no
# Default:
# TLSKeyFile=


### Option: TLSPSKIdentity
# Unique, case sensitive string used to identify the pre-shared key.
#
# Mandatory: no
# Default:
# TLSPSKIdentity=


### Option: TLSPSKFile
# Full pathname of a file containing the pre-shared key.
#
# Mandatory: no
# Default:
# TLSPSKFile=


####### For advanced users - TLS ciphersuite selection criteria #######

### Option: TLSCipherCert13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for certificate-based encryption.
#
# Mandatory: no
# Default:
# TLSCipherCert13=

### Option: TLSCipherCert
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for certificate-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL:+CTYPE-X.509
# Example for OpenSSL:
# EECDH+aRSA+AES128:RSA+aRSA+AES128
#
# Mandatory: no
# Default:
# TLSCipherCert=

### Option: TLSCipherPSK13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for PSK-based encryption.
# Example:
# TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA25 6
#
# Mandatory: no
# Default:
# TLSCipherPSK13=

### Option: TLSCipherPSK
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for PSK-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL
# Example for OpenSSL:
# kECDHEPSK+AES128:kPSK+AES128
#
# Mandatory: no
# Default:
# TLSCipherPSK=

### Option: TLSCipherAll13
# Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3.
# Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
# Example:
# TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA25 6:TLS_AES_128_GCM_SHA256
#
# Mandatory: no
# Default:
# TLSCipherAll13=

### Option: TLSCipherAll
# GnuTLS priority string or OpenSSL (TLS 1.2) cipher string.
# Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
# Example for GnuTLS:
# NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL:+CTYPE-X.509
# Example for OpenSSL:
# EECDH+aRSA+AES128:RSA+aRSA+AES128:kECDHEPSK+AES128 :kPSK+AES128
#
# Mandatory: no
# Default:
# TLSCipherAll=

####### For advanced users - TCP-related fine-tuning parameters #######

## Option: ListenBacklog
# The maximum number of pending connections in the queue. This parameter is passed to
# listen() function as argument 'backlog' (see "man listen").
#
# Mandatory: no
# Range: 0 - INT_MAX (depends on system, too large values may be silently truncated to implementation-specified maximum)
# Default: SOMAXCONN (hard-coded constant, depends on system)
# ListenBacklog=

#DisableActive=0
#DisablePassive=0

Also share the Item host configuration photo.

[Muhammad.qaseem]

Hi Vijayk,
I am facing same kind of issue but the version are different can there be version compatibility issue or not.
Below is the detail:
Zabbix agent:
zabbix_agent2 (Zabbix) 5.2.4
Zabbix Proxy:
zabbix_proxy (Zabbix) 6.0.10
Zabbix Server:
zabbix_server (Zabbix) 6.0.13

[alaahil]

Here you go

[vijayk]

Sorry, Please share the host configuration screenshot.

[vijayk]

@Muhammad.qaseem no it is not. Did you check in agent and server logs?

[alaahil]

Hello,

The host configuration snapshot is below:


agent logs on restarting the agent service on windows:
------------------------------------------------------------------------
4896:20231026:103258.050 agent #1 started [collector]
3948:20231026:103301.048 Unable to connect to [10.60.1.254]:10051 [cannot connect to [[10.60.1.254]:10051]: (null)]
3948:20231026:103301.049 Unable to send heartbeat message to [10.60.1.254]:10051 [cannot connect to [[10.60.1.254]:10051]: (null)]

Server logs:
---------------
nothing generated

[vijayk]

Unable to connect to [10.60.1.254]:10051

Did you test the port 10051 is open in zabbix server from the agent?

Use powershell to test the connection.

Test-NetConnection -P 10051 10.60.1.254

[alaahil]

Indeed there is a connection issue, I will try to resolve it and update you

[vijayk]

Indeed there is a connection issue, I will try to resolve it and update you

Okay, hope it'll fix your issue.

[alaahil]

Hello,
To give an update the issue is solved. The steps that I did:
1- open the port 10051
2- Install a listener at the zabbix server (not using proxies for the moment)
3- configure the active agent at port 10051.
Thanks a lot for your input that was beneficial

[solution]

Just to summarize the mode of operation:
For Active Mode/Agent:
If Zabbix Server is on the default port (10051)
on the agent side (zabbix_agent.conf):

...
# ServerActive=

ServerActive=10.60.1.254
---

If the Zabbix Server is on the custom port (Ex.: 35051)
on the agent side (zabbix_agent.conf):

...
# ServerActive=

ServerActive=10.60.1.254:35051
...

In both cases, if you have a firewall, the port must be opened on the zabbix server host.


Wellington